# Crate iter_num_tools

source ·## Expand description

## iter-num-tools

This is a collection if iterator extensions that make heavy use of number properties. Mostly extending on Range.

### LinSpace

LinSpace is an iterator over a range with a fixed number of values all evenly spaced.

```
use iter_num_tools::lin_space;
// Count from 1.0 up to and including 5.0, with 5 numbers counted in total
let it = lin_space(1.0..=5.0, 5);
assert!(it.eq([1.0, 2.0, 3.0, 4.0, 5.0]));
// Count from 0.0 up to and excluding 5.0, with 5 numbers counted in total
let it = lin_space(0.0..5.0, 5);
assert!(it.eq([0.0, 1.0, 2.0, 3.0, 4.0]));
```

### GridSpace

GridSpace extends on LinSpace.

```
use iter_num_tools::grid_space;
// count in 2 dimensions (excluding end points),
// from 0.0 up to 1.0 in the x direction with 2 even steps,
// and 0.0 up to 2.0 in the y direction with 4 even steps
let it = grid_space([0.0, 0.0]..[1.0, 2.0], [2, 4]);
assert!(it.eq([
[0.0, 0.0], [0.5, 0.0],
[0.0, 0.5], [0.5, 0.5],
[0.0, 1.0], [0.5, 1.0],
[0.0, 1.5], [0.5, 1.5],
]));
// count in 2 dimensions (including end points),
// from 0.0 up to 1.0 in the x direction,
// and 0.0 up to 2.0 in the y direction with 3 even steps in all directions
let it = grid_space([0.0, 0.0]..=[1.0, 2.0], 3);
assert!(it.eq([
[0.0, 0.0], [0.5, 0.0], [1.0, 0.0],
[0.0, 1.0], [0.5, 1.0], [1.0, 1.0],
[0.0, 2.0], [0.5, 2.0], [1.0, 2.0],
]));
```

### Arange

Arange is similar to LinSpace, but instead of a fixed amount of steps, it steps by a fixed amount.

```
use iter_num_tools::arange;
let it = arange(0.0..2.0, 0.5);
assert!(it.eq([0.0, 0.5, 1.0, 1.5]));
```

##### Note

There is no inclusive version of arange. Consider the following

```
use iter_num_tools::arange;
let it = arange(0.0..=2.1, 0.5);
```

We would not expect 2.1 to ever be a value that the iterator will ever meet, but the range suggests it should be included. Therefore, no RangeInclusive implementation is provided.

### ArangeGrid

ArangeGrid is the same as GridSpace but for Arange instead of LinSpace.

```
use iter_num_tools::arange_grid;
// count in 2 dimensions,
// from 0.0 up to 1.0 in the x direction,
// and 0.0 up to 2.0 in the y direction,
// stepping by 0.5 each time
let it = arange_grid([0.0, 0.0]..[1.0, 2.0], 0.5);
assert!(it.eq([
[0.0, 0.0], [0.5, 0.0],
[0.0, 0.5], [0.5, 0.5],
[0.0, 1.0], [0.5, 1.0],
[0.0, 1.5], [0.5, 1.5],
]));
// count in 2 dimensions,
// from 0.0 up to 1.0 in the x direction stepping by 0.5 each time,
// and 0.0 up to 2.0 in the y direction stepping by 1.0 each time
let it = arange_grid([0.0, 0.0]..[1.0, 2.0], [0.5, 1.0]);
assert!(it.eq([
[0.0, 0.0], [0.5, 0.0],
[0.0, 1.0], [0.5, 1.0],
]));
```

### LogSpace

LogSpace is similar to LinSpace, but instead of evenly spaced linear steps, it has evenly spaced logarithmic steps.

```
use iter_num_tools::log_space;
use itertools::zip_eq;
// From 1.0 up to and including 1000.0, taking 4 logarithmic steps
let it = log_space(1.0..=1000.0, 4);
let expected: [f64; 4] = [1.0, 10.0, 100.0, 1000.0];
assert!(zip_eq(it, expected).all(|(x, y)| (x-y).abs() < 1e-10));
// From 1.0 up to 1000.0, taking 3 logarithmic steps
let it = log_space(1.0..1000.0, 3);
let expected: [f64; 3] = [1.0, 10.0, 100.0];
assert!(zip_eq(it, expected).all(|(x, y)| (x-y).abs() < 1e-10));
```

## Traits

- Helper trait for
`arange`

- Helper trait for
`arange_grid`

- Helper trait for
`grid_space`

- Helper trait for
`grid_step`

- A helper trait for
`lin_space`

- A helper trait for
`log_space`

## Functions

- Create a new iterator over the range, stepping by
`step`

each time This allows you to create simple float iterators - Creates a grid space over the range made up of fixed step intervals
- Creates a linear grid space over range with a fixed number of width and height steps
- Creates a iterator over a range of arrays
- Creates a linear space over range with a fixed number of steps
- Creates a logarithmic space over range with a fixed number of steps

## Type Definitions

`Iterator`

returned by`arange_grid`

`Iterator`

returned by`grid_space`

`Iterator`

returned by [`grid_space`

]`IntoIterator`

returned by`ToArange::into_arange`

`IntoIterator`

returned by [`ToGridSpace::into_grid_space`

]`IntoIterator`

returned by`ToGridSpace::into_grid_space`

`IntoIterator`

returned by [`ToGridSpace::into_grid_space`

]`IntoIterator`

returned by`ToLinSpace::into_lin_space`

`IntoIterator`

returned by`ToLogSpace::into_log_space`